Everyone does things a little different, and that's OK. I would not bother with the SBUS for this plane. It is cheaper to just get the 8 or 14 ch receiver's. they are both high voltage and will give your servos higher speeds. 8 is enough for this, you can plug in the batt in the SBUS ch. Also, I prefer the Life batteries. A 3200ma Life goes for about $50 and can handle everything. Also I use a BIEC (batteries ignition elimination circuit) They are about $35, they plug into your receiver on the ch you choose as a kill. It regulates the voltage by choosing a jumper SW.
Here is how I am setting it up: CH 1&6 for ailr, 2 elev, 3 throttle, 4 rudder, 5 flaps, 7 choke, 8 kill. Power SBUS. (you can always use a manule choke and split the elev on two ch's) You can use two splitters for the two elev and flap servos. You might have to use a split reversing for the flaps.
The 8 ch rec is $130, the 14 is about $170, less with discounts. I dont use Futaba servos, I like to use Hitec. I am using the Hitec 5645's they are digital, metal gear, high tourqe, high speed for about $40 each. i think about using them in something different later down the road. A little overkill for this application maybe.
You will also need a fuel dot and install it at a level near the top of the tank. Not like some people do, lower down. The fuel will flow out before caping off.